metal end frame-compatible headphone holder

After you print this model in order to remove the supports from the roof of the print you will need to slide an exact knife under the supports on the roof of the print until they loosen up and then you can pull them away.
When you import the model into the slicer you you will have to select yes when it prompts you with a multi-part object detection warning. if you don't select yes it will import the lego piece of it separately and that's no good.

how to install it: 

push the model into the end frame and slowly wiggle it down until it sits in place at the bottom of the cutout. 

here is a video of how to install it: https://youtube.com/shorts/6VrywsuGpSY

this model can hold probably 5-10 pounds (I haven't tested it yet) so it should be able to hold almost any pair of headphones you have